It is common practice for therapists, physicians, athletes, and other individuals to utilize various electrical stimulation treatment and therapy devices to promote muscle training, conditioning, and growth. In addition, devices often referred to as transcutaneous electrical nerve stimulation (“TENS”) and microcurrent therapy units are employed to alleviate or eliminate pain and discomfort by blocking nerve signals from an affected area to the brain.
In pain management applications, electrical stimulation devices are used primarily to alleviate pain and discomfort, including chronic intractable pain, post-surgical pain, and post traumatic pain, and to increase blood flow. Increasing blood flow, for example, fosters healing. TENS, microcurrent, and other electrotherapy stimulation techniques have been used successfully for the symptomatic relief and management of chronic intractable pain for many years. In general, TENS or microcurrent electrical nerve stimulation controls pain of peripheral origin by providing a counter stimulation that interferes with the painful sensations.
For example, in one application of electrical stimulation according to gate control theory, small electrical impulses are sent through the skin into a painful area. These electrical impulses are harmless but reach the nerves and cause a mild tingling sensation. Gate control theory provides that as pain impulses travel through a nerve to the spinal cord and brain, the pain impulses can be altered or modified at certain points along the route. Pain signals are carried to the brain via small diameter, slow conducting nerve fibers. This transmission can be blocked by stimulating larger diameter, fast conducting nerve fibers. The signals traveling along the fast conducting nerve fibers normally reach the brain before those traveling along the slow conducting nerve fibers. If the larger fibers are stimulated without much activity of the smaller pain fibers, the “gate” is closed and pain is lessened and/or blocked.
Existing electrical stimulation devices used primarily to alleviate muscle pain or other discomfort, or to otherwise provide therapeutic treatment, typically comprise a stimulation unit coupled to an electrode or set of electrodes adapted to deliver stimulation treatment to the tissue of a user. Stimulation units can be large, table-top or freestanding devices, or relatively small, handheld or belt-mounted devices that are more easily portable. In either case, the units are generally used for some period of time, perhaps several minutes to about an hour, and then stored away when not in use. Many also require supervised use and treatment by a medical professional.
U.S. Pat. Nos. 6,002,965 and 6,282,448 disclose self applied devices and methods for prevention of deep vein thrombosis. The devices comprise an elongated rectangular cuff having fasteners and electrodes with an attached control unit for providing a predetermined electrical signal to the electrodes. The electrodes can also be combined with a motion detector for detecting muscle contraction.
Microcurrent and other therapeutic devices used for pain management are known in patch or bandage form, which are typically less obtrusive and expensive than the aforementioned stimulation units. These devices can easily be worn under clothing or otherwise applied to a user's tissue and left on for longer periods of time, from an hour to two or more days. The period of time for which such a microcurrent device can be left is typically dictated by the power source included with the device. While some microcurrent devices can receive power from independent and external sources, other microcurrent devices include an on-board power source, such as a coin-type battery.
For example, U.S. Pat. Nos. 6,408,211 and 6,606,519 teach microcurrent therapy devices for use in applying a DC current of less than one milliampere between two conductive pads through the tissue of a therapy recipient. The device can include an indicator such as an LED to provide an indication of imperceptible current flow, as taught by U.S. Pat. No. 6,408,211. Other microcurrent therapy devices and/or patch or bandage-type devices are disclosed in U.S. Pat. Nos. 3,472,233; 4,398,545; 4,982,742; 5,423,874; 5,578,065; 6,285,899; and 6,631,294.
Existing electrical stimulation devices, in particular those for pain management and control, suffer from several drawbacks. Microcurrent devices, while typically unobtrusive and convenient to use, generally do not excite nerves or stimulate muscles and therefore cannot provide the sensation and healing of TENS or other stimulation devices. Large and handheld devices, however, are cumbersome and do not provide extended treatment times in an unobtrusive and inexpensive manner. These devices also typically require a prescription or monitored use by a physician or other medical professional. Patch and bandage-type devices can offer more convenience, although the increased convenience typically comes at a higher cost. Further, patch and bandage-type devices do not provide control options; these devices instead deliver one treatment mode and intensity with no customization between on or off, or treatment area-specific modes or varieties.
Accordingly, for these and other reasons, a need exists in the industry for an inexpensive, compact, and controllable electrical stimulation device and method for therapeutic treatment and pain management.